766,569 research outputs found

    On foundational discretization barriers in STFT phase retrieval

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    We prove that there exists no window function gL2(R)g \in L^2(\mathbb{R}) and no lattice LR2\mathcal{L} \subset \mathbb{R}^2 such that every fL2(R)f \in L^2(\mathbb{R}) is determined up to a global phase by spectrogram samples Vgf(L)|V_gf(\mathcal{L})| where VgfV_gf denotes the short-time Fourier transform of ff with respect to gg. Consequently, the forward operator fVgf(L)f \mapsto |V_gf(\mathcal{L})| mapping a square-integrable function to its spectrogram samples on a lattice is never injective on the quotient space L2(R)/L^2(\mathbb{R}) / {\sim} with fhf \sim h identifying two functions which agree up to a multiplicative constant of modulus one. We will further elaborate this result and point out that under mild conditions on the lattice L\mathcal{L}, functions which produce identical spectrogram samples but do not agree up to a unimodular constant can be chosen to be real-valued. The derived results highlight that in the discretization of the STFT phase retrieval problem from lattice measurements, a prior restriction of the underlying signal space to a proper subspace of L2(R)L^2(\mathbb{R}) is inevitable.Comment: 19 pages, 3 figure

    Keadilan Gender dan Hak-hak Reproduksi di Pesantren

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    This study was intended to understand how the phenomenon of gender equity and . reproductive rights in pesantren using the theoreticalframework of attitude. The researchwas conducted in a qualitative approachthrough a case study method. Sources of data consisted of interviewed subjects, 18 FGD subjects, and survey of 327 subjects. Subjects were varying from pesantren\u27s supervisor, teacher, manager and doctor of pesantren\u27s Community Health Center, and santri itself. Data was also obtained from the observation of the supervisors\u27 behaviors and the pesantren\u27s environment. Subjects tended to agree in distinguishing the male andfemale gender role basedon what\u27s happening, different from the religious teachings they learned which tended to be gender fair. Regarding with women reproductive cases, subjects tended to be gender biased based on the interpretation of religious texts although they admitted that it was hard to be manifested in behavior, example: prefering monogamous marriage,never beating women, and not promoting early marriage. Subjects, agreed and understood that women had different, and yet more complex anatomical processes and functions, however their health service were just considered the same as men

    Own-language use in ELT: exploring global practices and attitudes

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    In this research paper Graham Hall and Guy Cook explore teacher attitudes to own-language use in the classroom. They conducted a global survey and interviews with practising teachers. They found evidence of widespread own-language use within ELT, and suggest that teachers’ attitudes towards own-language use, and their classroom practices, are more complex than usually acknowledged. The findings also suggest that there is a potential gap between mainstream ELT literature and teachers’ practices on the ground

    Heterogeneous out-of-equilibrium nonlinear q-voter model with zealotry

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    We study the dynamics of the out-of-equilibrium nonlinear q-voter model with two types of susceptible voters and zealots, introduced in [EPL 113, 48001 (2016)]. In this model, each individual supports one of two parties and is either a susceptible voter of type q1 or q2, or is an inflexible zealot. At each time step, a qi-susceptible voter (i = 1, 2) consults a group of qi neighbors and adopts their opinion if all group members agree, while zealots are inflexible and never change their opinion. This model violates detailed balance whenever q1 6= q2 and is characterized by two distinct regimes of low and high density of zealotry. Here, by combining analytical and numerical methods, we investigate the non-equilibrium stationary state of the system in terms of its probability distribution, non-vanishing currents and unequal-time two-point correlation functions. We also study the switching times properties of the model by exploiting an approximate mapping onto the model of [Phys. Rev. E 92, 012803 (2015)] that satisfies the detailed balance, and we outline some properties of the model near criticality

    Characterization of the nonequilibrium steady state of a heterogeneous nonlinear q-voter model with zealotry

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    We introduce an heterogeneous nonlinear q-voter model with zealots and two types of susceptible voters, and study its non-equilibrium properties when the population is finite and well mixed. In this two-opinion model, each individual supports one of two parties and is either a zealot or a susceptible voter of type q1 or q2. While here zealots never change their opinion, a qi-susceptible voter (i = 1, 2) consults a group of qi neighbors at each time step, and adopts their opinion if all group members agree. We show that this model violates the detailed balance whenever q1 ≠ q2 and has surprisingly rich properties. Here, we focus on the characterization of the model’s non-equilibrium stationary state (NESS) in terms of its probability distribution and currents in the distinct regimes of low and high density of zealotry. We unveil the NESS properties in each of these phases by computing the opinion distribution and the circulation of probability currents, as well as the two-point correlation functions at unequal times (formally related to a “probability angular momentum”). Our analytical calculations obtained in the realm of a linear Gaussian approximation are compared with numerical results

    DYNIQX: A novel meta-search engine for the web

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    The effect of metadata in collection fusion has not been sufficiently studied. In response to this, we present a novel meta-search engine called Dyniqx for metadata based search. Dyniqx integrates search results from search services of documents, images, and videos for generating a unified list of ranked search results. Dyniqx exploits the availability of metadata in search services such as PubMed, Google Scholar, Google Image Search, and Google Video Search etc for fusing search results from heterogeneous search engines. In addition, metadata from these search engines are used for generating dynamic query controls such as sliders and tick boxes etc which are used by users to filter search results. Our preliminary user evaluation shows that Dyniqx can help users complete information search tasks more efficiently and successfully than three well known search engines respectively. We also carried out one controlled user evaluation of the integration of six document/image/video based search engines (Google Scholar, PubMed, Intute, Google Image, Yahoo Image, and Google Video) in Dyniqx. We designed a questionnaire for evaluating different aspect of Dyniqx in assisting users complete search tasks. Each user used Dyniqx to perform a number of search tasks before completing the questionnaire. Our evaluation results confirm the effectiveness of the meta-search of Dyniqx in assisting user search tasks, and provide insights into better designs of the Dyniqx' interface

    Infant Care Review Committees: Their Moral Responsibilities

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